Compression results...

StangLou · Jan 14, 2006

Well I decided to do a little tinkering with the car today and wanted to check a few things. Ive been having some bluish smoke come out the tailpipes and wanted to check compression. I did this on a cold engine because those L/T's get HOT, but I know its not best for the results...

Cylinder 1. 128
Cylinder 2. 125
Cylinder 3. 130
Cylinder 4. 130
Cylinder 5. 125
Cylinder 6. 128
Cylinder 7. 125
Cylinder 8. 130

The weird thing is my plugs. The plugs in cylinders 1, 2, 5, and 6 look great. The plugs in 3 and 7 have a touch of oil around the base/thread (none on the porcelin/electrode), and plugs 4 and 8 have oil on the electrode and base.
Since the pressure in all cylinders were withing 10% of each other, I find it hard to think the piston rings could be shot.
I did make a goof during my lower intake install and didnt install the mesh filter below the pcv valve. I took off the air intake tube the other week and it had oil at the entrance to the TB, and there was visible oil in the TB going into the upper intake. I then realized I was a moron and didnt replace that screen. I got a new screen, and that really cut down on the smoke that was happening. That was about a week ago. I just changed the cars oil ~500 miles ago and the freaking oil light came on yesterday. It was about a quart low! I checked the air intake tube, TB, and upper intake, and there is no visible sign off oil . The only sign of oil is in those couple of plugs. How in the heck can this much oil get out, without me smoking out the neighbors, and people behind me?

Thanks for the help guys!

Black1987Stang · Jan 14, 2006

Numbers a little low but at least theyre all close of another. Did u do a wet test by putting a little oil in the cylinders, if the numbers go up it shows its the rings. A better thing to do would be a leakdown test, that will also show if any valves are leaking. Im not sure about the oil problem, My old motor used to smoke like a mofo, if i got on it i saw so much blue smoke in the rear view mirror and if i had gunned it and then came to a light all the blue smoke would just fly right past me . Even like this i only put a quart in it like every 2 weeks or so, u checked ur coolant? Even its not smoking i would say its leaking out somewhere

5.0Droptop · Jan 14, 2006

the oil may be sucking up thru the pcv and going thru the intake into the cyclinders. Its very common on the 5.0

86bluecobra · Jan 14, 2006

if you have cat's on your exhaust system a lot of times most of the oil you are burning gets burned to the point you don't see much. on my car when i had the factory h-pipe i never saw blue smoke. when i went to a O/R h-pipe it was a diffent story. some times going down a hill in forth gear it is embarissing at the bottom with my ehaust all loaded up with nasty burnt oilly blue smoke.

StangLou · Jan 14, 2006

the oil may be sucking up thru the pcv and going thru the intake into the cyclinders.

Thats my guess, especially since its the rear cylinders. Im guessing the pvc is just sucking it up and its wetting those plugs. Is there anything I can do to stop this?

Did u do a wet test by putting a little oil in the cylinders, if the numbers go up it shows its the rings.

I didnt man. I figured they were "low" since it was on a stone cold engine, I didnt feel like getting 3rd degree burns this am from the L/T's lol. Also, if that was the case, wouldnt the #'s in those cylinders be a bit higher than the dry cylinders?

if you have cat's on your exhaust system

Dont have those anymore, and I do agree with what you said. I never noticed a bit of smoke with my old factory catted mid, and the aftermarket catted mid I had on. Now is a different story. At start up there is smoke grayish/white smoke, just idling there was grayish/white smoke, matting the gas turned it a bit blue. I just dont know how Im loosing that much oil with that little puff that comes out when I mat it.
I fixed the oil leak I had, the pavement is dry as a bone now when I look under the car

u checked ur coolant?

Coolant level hasnt budged a bit.

5.0Droptop · Jan 14, 2006

On my stroker I moved the pcv to the valve cover and ran a hose from the original pcv location to the other valve cover. No more Sucky sucky.. LOL

dstanggt50 · Jan 14, 2006

Sounds like maybe a valve guide issue, I had a similar problem, blue smoke coming out of the tailpipes, and oil on some of my spark plugs, replaced valve guides, no problems since.

Compression results...

StangLou

Active Member

Black1987Stang

Active Member

5.0Droptop

...all those nights we shared, and you're a dude??

86bluecobra

Advanced Member

StangLou

Active Member

5.0Droptop

...all those nights we shared, and you're a dude??

dstanggt50

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Compression results...

StangLou

Active Member

Black1987Stang

Active Member

5.0Droptop

...all those nights we shared, and you're a dude??

86bluecobra

Advanced Member

StangLou

Active Member

5.0Droptop

...all those nights we shared, and you're a dude??

dstanggt50

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